1. Field of the Invention
The invention relates generally to the field of radio frequency (RF) communications. More particularly, the invention relates to RF antennas that can be detached from a wireless communication device, especially a personal data assistant.
2. Discussion of the Related Art
Prior art personal data assistants, sometimes called PDAs, are known to those skilled in the art. A transfer of data with a personal data assistant is typically enabled by physically connecting the personal data assistant to another electronic device (e.g., a personal computer) with a serial cable. The transfer of data can then take place between the personal data assistant and the other electronic device via electrical signals that are carried by the serial cable.
More recently, the transfer of data with the personal data assistant has become possible by optically connecting the personal data assistant to the other electronic device (e.g., a second personal data assistant). The transfer of data can then take place between the personal data assistant and the other electronic device via optical signals (e.g., infrared band) that are propagated through free space.
A problem with this personal data assistant data transfer technology has been that, for the transfer of data to take place, the personal data assistant must either be physically connected to the other electronic device or within a short line of sight distance to the other electronic device. Therefore, what is needed is solution that permits a transfer of data between the personal data assistant and another electronic device even when a physical or optical connection is not possible.
Meanwhile, it has been known in the field of communications to provide a radio frequency (RF) communications device with a compact antenna. Prior art RF communication devices, such as cellular phones, are known to those skilled in the art. Cellular phones are usually provided with a compact antenna. To minimize the overall size of such a communications device, these compact antennas are often provided in a deployable/retractable form so that the compact antenna can be at least partially withdrawn into the balance of the communications device during those times when data transfer it not needed. Cellular phones are typically provided with a longitudinally extending compact antenna.
A problem with this compact antenna technology has been that compact antennas are susceptible to mechanical failure. Repeated deployment and retraction of the compact antenna can lead to weakening of the mechanism and, eventually, breakage. Further, compact antennas are inherently fragile because of their small size and weight.
Despite their susceptibility to wear and damage, most compact antennas are not replaceable. Even in the case of compact antennas that are replaceable, the replacement operation is not easy and requires the use of tools to disassemble the communications device, replace the antenna subassembly, and then reassemble the communications device. Therefore, what is also needed is a solution that provides permits a compact antenna to be quickly and easily replaced by the end user of the communications device, without any tools.
Heretofore, the two requirements of wireless, beyond line of sight data transfer with a personal data assistant and easy replacement of a deployable/retractable compact antenna referred to above have not been fully met. What is needed is a solution that simultaneously addresses both of these requirements.